In packet-based networks, one measure of the quality of service provided to network users, is the packet loss ratio (PLR). PLR is the ratio of the number data packets lost to the total number of packets transmitted by the user into the network. In ATM it is also referred to as the cell loss ratio. The packet loss ratio (PLR) is one of the basic parameters in service quality and Service Level Agreements (SLA) and is notoriously difficult to measure.
Existing methods of measuring the packet loss ratio either use probes or collect hop-by hop measurement. Probes may be either active or passive. In either case they require the installation of dedicated equipment in strategic locations such as central offices. Such installations are costly. Additional installations are required as the network grows. In other words, the use of probes is not inherently scalable.
The second existing method of measuring packet loss requires the collection of hop-by-hop measurements. This requires detailed topology information and also requires cooperation of intermediate network operators. The packets may traverse networks that are owned by competing entities and one operator may not be willing to provide the hop-by-hop data necessary to measure the PLR.
It would be desirable to have a system and method that can measure the packet loss ratio for a service without requiring the sharing of data between networks or portions of a network.
Further, it would be desirable to have a method and system for measuring the packet loss ratio for a given service that is economical and does require the installation of active or passive probes.
Additionally, it would be desirable to have a system and method that is inherently scalable and does not require the installation of additional probes to be used in ever-larger networks.
Finally, it would be desirable to have a method and system that does not add additional traffic solely for the purpose of measuring packet loss.